This invention relates to a center-pull type calliper brake for a bicycle, and more particularly to a center-pull type calliper brake which has a fixing arm horizontally arranged, a pair of brake arms carrying brake shoes pivoted to both horizontal ends of the fixing arm, and a fixed bolt for fixing the fixing arm to the bicycle frame, so that a control wire is pulled to press the brake shoes against a wheel rim for exerting the braking action.
Conventionally, this kind of calliper brake is so constructed that the fixing arm is fixed to the bicycle frame through the fixed bolt, the brake shoes are attached to holders formed separately from the brake arms, at the utmost ends of the brake arms are formed bases for the holders, at the bases are formed slots extending vertically, and the holders are mounted through the slots in relation of being vertically adjustable respectively. Hence, the brake shoes carried by the holders are each vertically adjustable correspondingly to different brake mounting positions depending on the type and usage of the bicycle.
Accordingly, each of the brake shoes, which are adjusted in the mounting positions as described, changes its distance from the pivot position of each brake arm. As a result, the length of swinging motion of each brake shoe with respect to the stroke of the control wire is not constant when the wire is pulled for the braking action.
On the other hand, the center-pull type calliper brake spreads a center wire between the upper ends opposite to the brake shoe mounting ends at the brake arms, the center wire being connected with the control wire, so that the brake is complicated in construction and also troublesome in assembly.